Power sources, such as internal combustion engines and the like rely on the combustion of fuel and air as their primary source of energy.
In a standard four cycle engine, combustion occurs in the combustion chamber after the compression stroke when the fuel is ignited by various ignition methods.
The fuels that are most often used for power are hydrocarbon-based fuels such as gasoline.
The need for refinement of crude oil into the various octane levels required for present day engines is costly.
Environmental concerns require that improved efficiency and reduced emissions of harmful exhaust by-products be provided.
In present engines, when the piston reaches the top of its stroke, the fuel has been compressed and a single spark ignites the mixture of the compressed fuel and air and the speed of the flame front ignites the full mixture.
Lean air fuel mixtures do not burn well because the flame speed of the front is reduced.
The actual burning rate and ignition delay of this system depends upon the chemistry of the fuel and therefore extremely sophisticated combustion chambers have been necessary to produce slight improvements in ignition delay and burning rate.
Conventional ignition systems require relatively rich fuel mixtures for proper combustion.
Thus, the conventional ignition system and the speed of the flame front limits the useful operating range of both low and high compression engines.